Process of vulcanizing rubber



(No Modei.)

P. G. FOWLER. PROCESS OF VUIJOANIZING RUBBER.

Patented Oct. 28', 1890.

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UNITED STATES PATENT OFFICE.

FRANK G. FOIVLER, OF BRIDGEPORT, CONNECTICUT.

PROCESS OF VULCANIZING RUBBER.

SPECIFICATION forming part of Letters Patent No. 439,137, dated October28, 1890.

Application filed April 5, 1390- Serial No. 346,670. (No model.)

To all whom it may concern:

Be it known that I, FRANK G. FOWLER, of Bridgeport, in the State ofConnecticut, and a citizen of said State, have invented a new and usefulImprovement in the Process of Vulcanizing Rubber, of which the followingis a specification.

The primary vulcanize rubber goods uniformly. It also serves to preventthe formation of air-holes upon the surface of the goods vulcanized. Itis useful where the process of vulcanizing is by steam heat, andparticularly so where the steam is admitted direct into the receptaclewhich contains the articles to be vulcanized.

Notwithstanding vulcanization by the admission of steam direct to thearticles to be cured is the most satisfactory and extensively, usedprocess, yet as heretofore practiced it is found that it cannot beaccomplished uniformly, so that the goods will be homogeneous, and thatwhile an article in one portion of the vulcanizer is properly cured inanother portion it will be insufficiently cured and in another portionovercured, resulting in great loss and the product'on of inferior goods,which difficultieshavebaffled the skill of manufacturers up to thepresent time. My invention 0bviates these difficulties and renders thegoods uniform and homogeneous throughout. It is founded upon a discoverywhich I will first explain, and then describe a form of apparatus bywhich is may be applied to use; but it must be understood that I do notlimit myself to any form or arrangement of apparatus, since I believe myinvention to be broader than any form of apparatus and to be capable ofembodiment in a great variety of forms. IVater taken from a hydrant orwellsuch as is usually used for the purpose of supplying a boiler-holdsin solution a large quantity ofgases-suchasoxygen,nitrogen,carbonicacid, ammonia, &c.-a great number ofwhich may be held in solution at the same time. When water is evaporatedfrom a boiler for the purpose of supplying a vulcanizer those gases areexpelled from the water by the heat, and passed with the steam into thevulcanizer, where they remain as fixed gases, not condoes, when thetempera- Herein consists the pardensing, as the steam ture begins tolower.

object of my invention is to ticular discovery to which I refer-namely,if a chamber be filled with part steam and part gas its temperature willnot be uniform throughout, and the steam-gage will not always'determineits temperature; but if such vessel is filled with steam onlyand bysteam I mean the vapor of water its temperature will be uniform in everyportion, and a steam-gage attached at one point will truly indicate thetemperature of the chamber in every part, as the temperature willcorrespond with the steam-pressure.

My invention is founded on the discovery above outlined; and it consistssubstantially in removing the gases from it is used to produce steam inthe boiler and then passing the steam all freed from gases into thevulcanizer, whereby the same is provided with a perfectly-uniformtemperature throughout, in every portion of it, during the process ofvulcanization.

In the accompanying drawingl have shown by a diagram a generalarrangement of apparatus by which my invention may be practiced.

a is a pipe for the feed-water, communicating with a well or hydrant.

b is a vessel in which the water and its gases are separated. The gasesare drawn off through the pipe 0 by the air-pump d. The water runs 01fthrough the pipe 6 into a supply-tank f. Thence it is forced by thefeed-pump 9 into the boiler h, arriving there freed from gases.

4) represents the vulcanizing-chamber, and is provided with a cock p forblowing ofi the water of condensation. I

i is a pipe connected to the boiler and communicating with thevulcanizer for the admission of steam for the purpose of curing thearticles to be vulcanized.

7c and k is a pipe communicating between the vulcanizer and the receiverof the airpump, by means of which the air can be exhausted from thevulcanizer.

I carry my invention into effect as follows: When the boiler h is firstfilled with water, the gases are removed from it by means of theair-pump d, which communicates with the boiler through the pipe 10, andafter that is done the gases are removed from the feed- Ice water in thevessel b, so that no more gases can enter the boiler. Steam may then begotten up on the boiler h, and after the articles prepared and placed inwhich communicates between the vulcanizer and the receiver of theair-pump 61. Steam is then admitted to the vulcanizer, and the air beingalready out it at once 'envelops all the articles to be vulcanized, sothat they all start with the same degree of heat. As there is nothingadmitted into the vulcanizer but the vapor of water, the heat is uniformand constant in all parts of the vulcanizer, and the goods arehomogeneous and uniform when completed and their surfaces free fromairholes. A steam-gage attached to the vulcanizer indicates the exacttemperature in all parts of the vulcanizer, and the attendant canthereby ascertain just how long the process should be continued toeffect a proper cure. The air can be blown out in the ordinary mannerthrough the cook 19; but I prefer Where great uniformity andhomogeneousness are required to remove it by the air-p11 mp.

The method of removing the gases from the water above described is thesame as set forth in patents issued to me and numbered 346,198 and377,099; but other methods may be used-for example, that described inPatent No. 423,423. This process can also be ap- I plied beneficiallyfor the purpose of heating vulcanizingpresses or calender-rolls wherethe steam does not come in direct contact with the articles to bevulcanized.

I claim as my invention- The process of vuloanizing rubber or otheranalogous substances, which consists in separating the gases from thewater before it is used to produce steam and then passing the steam allfreed from gaseous substances into I the vulcanizer, whereby the same ismaintained at a uniform temperature in all its parts during the processof vulcanization and the goods cured alike and rendered homogeneous inquality, substantially as set forth.

FRANK G. FOXVLER.

